1. Field of the Invention
This application relates generally to windscreen wiper devices for vehicles.
2. Related Art
Conventional-style wiper blades typically include a frame-like superstructure which includes a plurality of reciprocating yokes which are configured to bias the length of a wiper element against a curved windshield. Such conventional-style wiper blades may be detrimental in icy conditions because ice or other debris can form or otherwise get caught in the superstructure, thereby compromising the superstructure's ability to bias the wiper element against the curved windshield, which will diminish wiping performance. One approach some wiper blade manufacturers have taken to solving this problem of reduced performance in icy conditions is to place a cover or shroud around the superstructure to protect it from ice.
As an alternative to the conventional blade with a shroud approach, wiper blade manufacturers have developed beam-style wiper blades which utilize a pre-curved carrier of a spring-like material for biasing the length of the wiper element against the windshield rather than the superstructure found on conventional-style wiper blades. Such beam-style blades typically also include a spoiler which is shaped for improving the seal between the wiper element and the windshield while the vehicle is travelling at speed. However, there remains the problem of selecting what material to be used for the spoiler. A relatively softer material may allow for sufficient flexibility of the carrier and the wiper element but may be susceptible to damage from ice scrapers or other ice formation in cold conditions. On the other hand, a relatively harder material might be resistant to damage but may impede flexing of the carrier and wiper element, thereby compromising the performance of the wiper blade.